The invention is based on a waveguide switch of the type including a housing having an axial bore and provided with at least four waveguide ports which each communicate with the bores have a rectangular cross section and which are all arranged in one plane transverse to the longitudinal axis of the bore and at right angles to one another, a cylindrical rotor disposed in the bore of the housing and provided with three waveguide passages having a corresponding rectangular cross section so as to produce different waveguide connections between the waveguide ports in certain rotor positions, with one of the waveguide passages being configured as a straight central passage and with the other of the waveguide passages being disposed on respectively opposite sides of the straight waveguide passage and each producing a deflection of the waveguide path by 90.degree..
Such a switch is known, for example, from DE-OS 3,441,728. In this prior art waveguide switch, the rotor is provided with three waveguide passages which are parallel to one another. Although the manufacture of such waveguide passages is rather simple, it has been found that, particularly at the junctions between rotor and stator, the bend in the waveguide path produces relatively high reflections. To improve transmission characteristics, it is advisable to give the two outer waveguide passages an arcuate shape (similarly to the configuration in DE-OS 2,924,969). However, the small dimensions of a miniaturized waveguide switch do not permit such an arcuate configuration.